1H NMR and FT-IR dataset based structural investigation of poly(amic acid)s and polyimides from 4,4′-diaminostilbene

Structural investigation of polymers by various available analytical methods is important in order to correlate the structure with polymer properties for which understanding of polymer structure is very important factor. The data presented here in this article shows the 1H NMR spectra used for the characterization of prepared poly(amic acid)s (PAAs). It is often difficult to assigns the peak in NMR of polymers due to its complexity. Data presented here helps in assigning the proton peak in complex NMR of PAAs prepared from aromatic diamines. Further functionality in polymer chains can be confirmed by FT-IR spectra. Change in functionality during some reaction or process can be monitored by disappearance or appearance of peaks in FT-IR. The complete imidization of PAAs to Polyimides (PIs) is difficult to analyze because of the chemical stability i.e. insolubility of PIs in most of the solvent therefore the completion of imidization process was confirmed using FTIR.


a b s t r a c t
Structural investigation of polymers by various available analytical methods is important in order to correlate the structure with polymer properties for which understanding of polymer structure is very important factor. The data presented here in this article shows the 1 H NMR spectra used for the characterization of prepared poly(amic acid)s (PAAs). It is often difficult to assigns the peak in NMR of polymers due to its complexity. Data presented here helps in assigning the proton peak in complex NMR of PAAs prepared from aromatic diamines. Further functionality in polymer chains can be confirmed by FT-IR spectra. Change in functionality during some reaction or process can be monitored by disappearance or appearance of peaks in FT-IR. The complete imidization of PAAs to Polyimides (PIs) is difficult to analyze because of the chemical stability i.e. insolubility of PIs in most of the solvent Data is with this article.

Value of the data
This following data helps in assigning the proton peak which is otherwise a complex task in case of polymers.
The comparison with various other polymers can help in understanding the significant role of aromatic diamines and dianhydride structure in structural-property of polymers.
The completion of imidization can be easily confirmed by FT-IR by comparing the spectra before and after imidization process.

Experimental design, materials and methods
For NMR DMSO-d 6 was used as a solvent at 23.1°C with 16 accumulation scans, using the proton resonance of residual non-deuterated DMSO as an internal standard (2.55 ppm). PAAs and PIs film of   thinkness 30-45 mm was used for FT-IR analysis. PAA film of thickness 30-45 mm was obtained by dissolving polymer fibrils in DMAc/DMF forming a yellow solution, poured on a silicon wafer/aluminum plate by spin coating and dried by heating over hot plate. Polyimide (PI) films were obtained by stepwise thermal imidization of the PAAs film in an oven for 1 h each at 100, 150, 200 and 250°C, respectively, under vacuum [3].